A typical foldable supporting frame is made of two frame units, each having an upper frame and a lower frame. The upper and lower frames of the two frame units are pivotally connected to each other through a plate formed with pivotal holes. An example of such a supporting frame is disclosed in U.S. Publication No. 2013/0067862. To facilitate the folding and unfolding of the supporting frame, the pivotal holes for connecting the upper frames of the two frame units are generally positioned with a distance different from that of the pivotal holes for connecting the lower frames of the two frame units. This requires a large plate, sufficiently wide and long for the formation of the pivotal holes, and thus increases the overall size and weight of the foldable supporting frame. In addition, as the upper and lower frames of the two frame units rotates around the pivotal holes formed on the plate, folding and unfolding of the supporting frame is not smooth. The supporting frame when folded is not compact.
Given the current state of the art, there remains a need in the art for supporting frames and related components that are stable, easier to use, and configured for convenient packaging, shipping and transportation.
The information disclosed in this Background section is provided for an understanding of the general background of the invention and is not an acknowledgement or suggestion that this information forms part of the prior art already known to a person skilled in the art.